Time course for blood pressure lowering of dihydropyridine calcium channel blockers
Niousha Ghamami1, Sandy Hsiang Yu Chiang, Colin Dormuth
1Biology and Pharmacology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada, L8S 4L8.
Insights
Dihydropyridine calcium channel blockers provide a consistent blood pressure lowering effect over 24 hours. Further research is needed to understand the clinical benefits and harms of this stable antihypertensive effect.
Area of Science:
- Pharmacology
- Cardiovascular Medicine
- Clinical Trials
Background:
- Calcium channel blockers (CCBs) are essential antihypertensives, with dihydropyridine and non-dihydropyridine subclasses.
- A comprehensive analysis of the 24-hour blood pressure-lowering profile of CCBs is lacking.
Purpose of the Study:
- To evaluate the hourly variation in blood pressure reduction by dihydropyridine CCBs over 24 hours.
- To assess the consistency of antihypertensive effects in patients with hypertension.
Main Methods:
- Systematic review and meta-analysis of randomized, placebo-controlled trials.
- Included trials used ambulatory blood pressure monitoring (ABPM) in adults with hypertension.
- Searches conducted across major databases (CENTRAL, MEDLINE, EMBASE, ClinicalTrials.gov).
Main Results:
- Sixteen trials with 2768 participants were included, assessing amlodipine, lercanidipine, mandipine, nifedipine, felodipine, and nicardipine.
- Dihydropyridine CCBs demonstrated a stable blood pressure-lowering effect throughout the 24-hour dosing interval.
- No clinically significant hourly variations in systolic or diastolic blood pressure reduction were observed, though a moderate risk of bias was noted.
Conclusions:
- The studied dihydropyridine CCBs exhibit a consistent hourly blood pressure-lowering effect over 24 hours.
- The clinical implications, benefits, and harms of this stable antihypertensive pattern remain undetermined.
- Further trials require precise recording of drug intake times and hourly blood pressure standard deviations to clarify effects and adverse events.
Background:
Calcium channel blockers are a heterogeneous class of drugs, including dihydropyridine and non-dihydropyridine subgroups, commonly used in the treatment of hypertension. A systematic review of the 24-hour time course of the blood pressure-lowering effect has not been published.
Objectives:
To assess how much variation there is in hourly systolic and diastolic blood pressure lowering by dihydropyridine calcium channel blockers over a 24-hour period in people with hypertension aged 18 years or over, with baseline systolic blood pressure of at least 140 mmHg or diastolic blood pressure of at least 90 mmHg, or both.
Search Methods:
We performed electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1, 2014), MEDLINE (1946 to February 2014), EMBASE (1974 to February 2014), and ClinicalTrials.gov (to February 2014). We also screened references of published studies and reviews to identify additional trials.
Selection Criteria:
We included all randomized, placebo-controlled trials assessing the hourly effects of dihydropyridine calcium channel blockers by ambulatory blood pressure monitoring in adults with hypertension with a follow-up of at least three weeks.
Data Collection And Analysis:
Two authors independently selected the included trials, evaluated the risk of bias, and analyzed the data.
Main Results:
We included 16 randomized controlled trials of dihydropyridine calcium channel blockers in this systematic review, with 2768 randomized participants. Drugs studied included amlodipine, lercanidipine, mandipine, nifedipine, and felodipine (all administered once daily) and nicardipine (administered twice daily). We analyzed and presented data by hour post dose. The blood pressure-lowering effect was stable over time; there were no clinically important differences in blood pressure-lowering effect of calcium channel blockers between each hour for either systolic blood pressure (estimated mean hourly differences ranged between 9.45 mmHg and 13.2 mmHg) or diastolic blood pressure (estimated mean hourly differences ranged between 5.85 mmHg and 8.5 mmHg). However, there was a moderate risk of bias for this finding. Once-daily dihydropyridine calcium channel blockers appeared to lower blood pressure by a relatively constant amount throughout the 24-hour dosing interval.
Authors' Conclusions:
Six dihydropyridine calcium channel blockers studied in this review lowered blood pressure by a relatively similar amount each hour over the course of 24 hours. The benefits and harms of this pattern of blood pressure lowering are unknown. Further trials are needed with accurate recording of time of drug intake and with reporting of standard deviation of blood pressure at each hour. We did not attempt to assess adverse effects in this review due to the lack of reporting and the short duration of follow-up.
Related Concept Videos
01:18Antihypertensive Drugs: Action of Calcium Channel Blockers
01:20Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
01:15Antihypertensive Drugs: Thiazide-Class Diuretics
01:25Antianginal Drugs: Calcium Channel Blockers and Ranolazine
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...
01:28Hypertension IV: Drug Therapy and Lifestyle Modifications
01:22Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...